Protein polymerization induced by cytotoxic amines in vitro will be studied to determine to what extent this reaction is the mechanism of cytotoxicity in vivo. Studies on active uptake mechanisms found in the plasma and vesicular membranes of sympathetic neurons with special emphasis on the interaction of radioactive cytoxic amines will be continued. Localization of membrane bound catechol-O-methyltransferase with immunofluorescence, immunoperoxidase and immunoferritin techniques to determine both the regional and cellular distribution of this enzyme will be continued. The induction of increased enzyme levels by nerve- growth factor, pharmacological parameters and receptor supersensitivity induced by electrolytic and chemical denervation will be explored. The binding and release of norepinephrine as influenced by drugs will be explored further, as will interactions of certain amines and drugs at storage and receptor sites. Studies on inhibitors of tyrosine hydroxylase, phenylalanine hydroxylase, dopamine-beta-hydroxylase and catechol-O-methyl-transferase will be continued. The incorporation of fluorohistidines into protein will be studied with in vitro systems for protein synthesis.